Help ( long distance toxic ?)

So my boyfriend is gone away for 2 weeks and I’ve had boyfriends before where they go away and such.

its been about 4 days sense hes left and a lot seems a bit off

The texting

The way he texts me is different

I feel as if he’s lost interest

He don’t put effort into our text messages at all or even on FaceTime

Well just be sitting there not saying anything unless its me who brings stuff up

He’s just been weird and I been having tons of anxiety about it maybe I’m just crazy but is there any thing to look out for in this long distance relationship?

Am I over reacting and maybe just stressed, idk :(

I’m just scared these are signs of it turning bad or toxic...